8"w X 22"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 9.75"w x 23.75"h] Supply Grille + Product Details Outer dimensions:

+ Product Details Outer dimensions: 21

Actual Filter Size – 29 3/4"w x 23 3/4" x 1"

Rigid Gauge Steel

+ Product Details Size – 18"w X 8"h is the size for the duct opening measurement only

+ Product Details Size – 20"w X 24"h is the size for the duct opening measurement only

8"w X 22"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 9.75"w x 23.75"h] Supply Grille + Product Details Outer dimensions:+ Product Details Size 8"w X 22"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 9. 75" Width X 23. 75" Height Weather and Pest Proof These louvers are especially designed to prevent water from entering your home, and with a built in back 1 2" mesh they also protect you from annoying rodents like mice, rats, birds, and squirrels High Quality Aluminum The premium durable aluminum will never rust and it will never wear